Solar cells can eliminate the need for grid-tied electrical power. The amount of expensive solar material may be overdesigned to handle all boundary conditions, such as fifteen straight days of heavy overcast weather, to ensure reliability. The additional solar material needed to handle the boundary conditions may be too expensive and lead to a decision not to use a solar powered solution.
In some solar cell based solutions, the solar cells are coupled to the grid to feed power back into the grid when more power is produced than needed. Complex and expensive switching circuitry may be needed to disconnect the solar cells from the grid when excess power is not being produced.